1. Field of Invention
The present invention relates to pumps and, more particularly, is directed towards devices for circulating fluids.
2. Description of the Prior Art
Pumping devices of various configuration have been designed for circulating fluids. One type of pumping device involves the use of a pair of diaphragm pumps which are remotely coupled by a conduit containing an intermediate liquid. The volume of the intermediate liquid in the conduit and chambers of both pumps changes with temperature variation which results in unstable operation of the device. Such pumps have been introduced with varying degrees of success.